Relief valve for air filters



Nov. 18,1952 c. J. GLANZER 2,618,289

' RELIEF VALVE FoR AIR FILTERS Filed Jan. 20, 1950 2 SHEETSSHEET 1 INVEN TOR. CLARENCE J. GLANZER AT TOR NEYS v Nov. 18, 1952 c, J, GLANZER2,618,289

I RELIEF VALVE FOR AIR FILTERS Filed Jan. 20, 1950 SHEETSSHEET 2INVENTOR. CLARENCE J. GLANZER W/MMMM ATTORNEYS Patented Nov. 18, 19522,615,289 RELIEF, VALVE FQR. AIR FILTERS Clarence'J. Glanzer,Nortlifield, Ohio, assignor to Air-Maze 'CorporatiomCleveland, Ohio, acorporation of Delaware Application January 20, 1950, Serial No. 139,578

1 This invention relates to a reliefvalve. means where sudden changesfrom suction to pressure occur in a conduit connection and wherein it isdesired to quickly relieve a pressure condition in the conduitconnection, and at the same time to positively prevent the transmissionof .the pressure beyond the relief device. i One of the applications ofthe present invention occurs in connection with an air filter of theliquid-washed type as applied to the suction pipe of an air compressorof the free-unloading type. When a filter is connected in this fashionand the compressor is unloaded (particularly at higher speeds), there isa sudden-rush lofair under pressure upstream offlthe inlet pipe, .andthis generallyblows the liquid out of the.. liq uiclwashed filter. rAnother application of I the: inventionewould occur where an-aircleaning filterofthe liquid.- washed'type was applied to the air inletofan internal combustion engine. When .a backfire occurs in the engine,there is a te'ndencyto. blow the liquid out of the filter. In the abovementioned illustrative. examples of the application of my invention,.itis desirable to relieve the pressurein .the.inlet...pipe (which isnormally subjectto suction) the moment the pressure occurs. At the sametime, it is :desi'rable to prevent the transmission f the pressure tothe filter so as to prevent any spilling or blowing out of the liquidfrom the filter. The present invention is adapted toaccomplish....these;..purposes; v.I Other object and advantagesotmy.invention will-be apparent from the accompanying descriptionl anddrawings, and the essential features thereof will be set forth in theappended claims. ln' the drawings .j I v.

1.21s a side elevational viewlpartly broken away in central sectionshowing a liquid-washed air filter in combination with my improvedrelief valve r neans; I Fig-'24s a view' similar to the lower-portion ofFig.1 but" showing the 'partsin another position; while v 1 "g. 3 isa-transverse sectional view taken generally alongthe line 3- 3 'of Figl1.

In the embodiment 'of my invention chosen for illustration in Figs. 1'and 2, I have shown the conduit connection Ill which is the inletpipeifor an air compressor of the free-unloading type? The filter is forthe purpose of cleaning the airnorn ally sucked through the connectionHl 'to the compressor. 1 have chosen to illustrate a filter'of' a knowntype for coaction with 'my 5 Claims. (Cl. 137493) improved relief valvemeans, but it should bounderstood that many other types of filters mightbe used in the same location and my invention'is useful therewithinsofar as it prevents th'e'spilling' or blowing of liquid out of theliquid bath "of the filter. The type of filter illustrated is filledwith a liquid such as oil up to the level of the bead I2 which, when noair is flowing. fills the bowl I3 from outer wall to outer wall up'tothis which depends. downwardly from theicover member to a level justslightly belo'wthebead I2. It should be understood that'the outermostlayers ofthe filter element l5 are of very coarse ma 1 terial so thatthe entering air stream intermixed 'with. the. oil from the bathiscarried. upwardly inside. of. the skirt l6 and evenly distributedoverthe filter element. To provideva .seal,.a.strip.iof

"air impervious material I! extending in a .cylin+ drical form entirely.around the filter element I5 is provided near the bottom between. layersof the screen material of the filter element; .Centrally of the bowl l3thereis provided aflcyline drical outlet pipe l8. In the normalvuseofxthe filter, air entering the. filterinlet betweenithe covers l4and bowl l3,,-flows in thei directionfof the arrows down through thechamber ,I 9,;:..then' beneath the surface of the oil, earrying oilwithit to wash the filter element .l5. The'a-irpasses above the battle. I!and through the centralportion of the filter to theupper end of tube lgand then downwardly toward'the outlet. Usually- -oilreturns from thechamber radiallyinwardlypf baffle IT to the chamber radially outwardlythere- I from either through openings in the battle [1 or by tricklingover the top thereof. S uch filt er action'iswell knownfl It isobvious-that in apparatus of this kind, upon the occurrence oi -a suddenpressure in theconduit connectionit;

-. air will fiow in a direction reverse to thearrows indicated in Fig. 1and will blow oil or other liquid from the bath in the bottom-of bowl l3upwardly through the chamber. 19 and out to the atmosphere. It is thepurpose of'my in en tion to prevent this; i

Between the conduit connection In ter (more particularly the outletconduit 1810f,

the filter) I place my improved pressure relief device. In the form hereshown, this'cofnprises a spider 20 having radial arms are. and a centralopening through which passes a bolt 2 lftliehead tion 23b as clearlyshown in Figs. 1 and 3.

of which is secured as by welding to the center of the spider 20. Thespider has a cylindrical side wall 2% adapted to telescopically enterthe 1 ing a central opening of approximately the same 7 diameter as theinside opening of, tube 18. A

lower subassembly is provided with an upstanding central cylindricalnose 23a which extends inside of the opening of flange 22b The sameplate member of the lower subassembly then extends radially outwardly asindicated at 231) for a dis-- tance a little more than one-fifth of thediameter of the relief valve member. member then bends downwardly for ashort distance; as indicated at 23c and then a slight shoulderoutwardlyconnects the same with-a further downwardly extending imperforatemember2301, the bottom end of which terminates in a flange 23c extendingradially outwardly. A plurality of openings. 24 is provided through theplate por- Secured to the flange 23c is a bottom housing cover 25vofannular form secured to the plate member 23c .as by spot welding. Thishousing member form have their upper flanges'26a secured as byspotrwelding'to the plate portion 23b and have their lo'werrflanges 26bsecured as by spot welding to a plate of expanded metal 21 orsimilar'stifi foraminousmaterial. An annular flexible valve 2830frubberlike material lies on top-of the expanded metal plate 21 andis'provided with a central opening to receive the bolt 2 I. A washer 29and a nut 30 threaded on the lower end of bolt 2| of" smallerdiameterand threaded as indicated at 2.10; holds the parts assembled onbolt 2 I For mounting all of the parts on the pipe or conduit I0, Iprovide a special fitting 3! having alower threaded sleeve'3la having athreaded connection with the conduit H). A flange 31b extends-radiallyoutwardly for the purpose 'of holdin'g a gasket 32 between the member 3|and the lower housing cover 25a.- An upstanding central'sleeve or nozzle3|]c, of approximately the same "diameter as tube 18, extends upwardlythroughthe central opening internally of "the flange 25c. A spider 3 Idis provided with a central hub 3| e Which'carries a thread to receivethe end Zia of bolt2l.

As the upper 'suba's'sembly and the lower subassembly are securedtogether, an annular resilient rubberlike valve 33 is placed over theopenin s 24 so as to close the same, this valve extending from theshoulder 23c inwardly almost to the nozzle provided by the upstandingflange 23a. The inner periphery of this valve 33 is clamped between theflange 22b of the upper as sembly and the plate portion 23b of the lowerassembly as the two parts are drawn together. At the same time, a filterelement 34 is clamped between the top and bottom housing members 22 and25 respectively. This filter element is of annular nature and extendsentirely around the relief valve device for the purpose of filteringdirt out of any air which may enter the device The same plate 4 radiallyat this point. The filter 34 may be of any known type and is here shownas composed of several layers of screen mesh material.

The relief valve device and the filter are held together by means of abolt 35 having a thumbscrew head 35a extending out the top of thefilter. The lower end of bolt 35 is threaded and enters a threadedopening 36 at the upper end of bolt 2|.-

In the normal condition of the relief valve, as shown in Fig. 1, whenthe air is entering the compressor in the direction of the arrows ofFig. 1, the valve 33 covers the openings 24 and is held there bythe-suction in conduit I 0. At the same time; the valve 28 covers theopenings in the expanded metal plate 21 due to the downward rush of airthrough the device. Upon the occurrence of a sudden backflow of air, inthe direction of the arrows of Fig. 2, such as occurs in the unloadingof a compressor of the type described,- the rushof air upwardly throughthe openings in theexpanded metal and in the directionof the arrows 31of Fig; '2 pushes upwardly on thevalve 28 and carries the same to thepositionsshown in Fig. 2 where valve 28 is arrested by having its outeredges strike against the lower surface of plate portion 23b; Thiseffectively shuts ofi any counter-flow of air through the tube l8 intothe filter device and therefore no oil will be blownout of the oil bathof the filter. .At the same time, the sudden air pressure beneath thevalve .33 acting through the "openings 24 lifts valve 33 to-thepositions shown in Fig. 2 giving free exit of the air outwardly throughthe filter element 34 to atmosphere. Thus my device operates effectivelyto positively block the backflow of air through the filter and at thesame' time provides easy exit of the air to the atmosphere, thuseflectively relieving the pressure in the conduit Hi. Inactual'practice, as well known to those in this art, the valve 33 willflutter according to the strokes of the compressor during the unloadingcycle. However, all pressure inthe conduit lll'will be relieved throughthe valve 33. It is the first sudden rush of air Which'must be takencare'of as the compressor is unloaded and this effectively moves thevalves 28 and 33 from the positionpf-Fig. 1 to the position of Fig. 2 soas;v

to effectively carry pressure. What I claim is: 1.' A pressure fluidstream relief device com prising a housing adapted to be positioned in agaseous stream and having a normal inlet located centrally of its topWall and having anormal outlet lo'cated centrally of its bottom-wall,said relief device being subjected at times to' back flow whereupon saidnormal outlet becomes an inlet. a nozzlea't said normal outlet fordirecting a gaseous jet upwardly during back flow, a foraminoushorizontally extending planar' valve support spaced above said nozzle ashort distance, said valve support having large through openings, atfree planar check valve normally 'lying on top of said support, saidcheck valve having width dimensions greater than said normal inlet, saidnormal inlet providing a downwardly presented valve seat against whichsaid check valve is adapted to seatv upwardly under influence of agaseous -jet fromsaid nozzle during back flow.

out the desired relief of said housing forming a continuous conduit fromsaid normal inlet to said normal outlet, there being a fiat horizontallyextending wall of said housing havin relief openings through it, saidlast named wall being above and laterallyoutof flexible rubberlikematerial resting against said fiat wall and normally closing saidopenings, the inner edge only of said relief valve being secured to saidflat wall, and there being a passageway for free flow of the stream fromsaid normal inlet to said normal outlet around the outer periphery ofsaid check valve.

2. The combination of claim 1 wherein said housing includes an uppersubassembly having a centrally located upstanding nose adapted totelescopingly enter a connecting tube, a spider across the upper end ofsaid nose, an annular flange extending downwardly below said nose andhaving a diameter approximately equal to that of said normal inlet, alower subassembly including said fiat wall, said flat wall and reliefvalve being anflow whereupon said normal outlet becomes an inlet, anozzle at said normal outlet for directing a gaseous jet upwardly duringback flow, a foraminous horizontally extending planar valve supportspaced above said nozzle a short distance,

7 said valve support having large through openings,

nular with an inside diameter approximately equal to that of said normalinlet, a rigid connection between said flat wall and said valve support,there being registering central openings through said valve support andsaid check valve, and a vertically positioned bolt secured between saidspider and said valve support and clamping them together, whereby tohold said upper and lower subassemblies together, the inner periphery ofsaid relief valve being held clamped between .said annular flange (belowsaid nose) and said cated centrally of its top wall and having a 4normal outlet located centrally of its bottom wall, said relief devicebeing subjected at times to back a free planar check valve normallylying on top of said support, said check valve having width dimensionsgreater than said normal inlet, said normal inlet providing a downwardlypresented valve seat against which said check valve is adapted to seatupwardly under influence of a gaseous jet from said nozzle during backflow, said housing forming a continuous conduit from said normal inletto said normal outlet, a wall of said housing having at least one reliefopening through it, said last named wall being above and laterallyoutwardly from said check valve, a relief valve normally closing saidopening but uncovering said opening during back flow, and there being apassageway for free flow of the stream from said normal inlet to saidnormal outlet around the periphery of said check valve.

5. The combination of claim 4 wherein said housing includes a verticalrod extending up from said check valve support into said normal inlet,said check valve having a hole loosely surrounding said rod whereby theupwardly directed jet Will move said check valve along said rod intosealing engagement with said valve seat.

CLARENCE J. GLANZER.

REFERENCES CITED The following references are of record in the file ofthis patent:

UNITED STATES PATENTS Number Name Date 947,536 Wenkel Jan. 25, 19102,152,422 Torheim Mar. 28, 1939 2,196,287 Baudette Apr. 9, 1940

